java-dsa-practice/firstandlastelementinSortedArray.java at main · Arjunuk1/java-dsa-practice · GitHub

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public class firstandlastelementinSortedArray {
        public int lowerBound(int arr[], int t, int n){
        int s = 0;
        int e = n-1;
        int m = 0;
        int f = -1;
        while(s<=e){
            m = s+(e-s)/2;
            if(t == arr[m]){
                f = m;
                e = m-1;
            }
            else if(t<arr[m]){
                e = m-1;
            }
            else{
                s = m+1;
            }
        }
        return f;
    }
    public int upperBound(int arr[], int t, int n){
        int s = 0;
        int e = n-1;
        int m = 0;
        int f = -1;
        while(s<=e){
            m = s+(e-s)/2;
            if(t == arr[m]){
                f = m;
                s=m+1;
            }
            else if(t<arr[m]){
                e = m-1;
            }
            else{
                s = m+1;
            }
        }
        return f;
    }
    public int[] searchRange(int[] nums, int t) {
        int n = nums.length;
        int ans[] = new int[2];
        ans[0] = lowerBound(nums, t, n);
        ans[1] = upperBound(nums, t, n);
        return ans;
    }
}